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Vector Basics
What the heck is a vector? Can you hold it? No. Can you watch it? No. Does it do anything? Well, not really. A vector is a numerical value in math and physics. The value describes a specific amount of force and its direction. You need both of those values to have a vector. Both. Very important. Scientists refer to the two values as direction and magnitude. The alternative to a vector is a scalar. Scalars are values that have no direction. Temperature or mass are examples of scalars.
So you're driving at thirty kilometers an hour (30 km/hr). What's the vector? You can't know the vector if you only have one value (either amount or direction). In this example, you were never told about the direction.
When you see vectors in physics, they are usually lines with little arrows on the end. The direction of the line is the direction of the value and the length of the line depends on the amount of your measurement. If you're moving at 30 km/hr in a northern direction then you would have an arrow pointing straight up with a length of 30.
Combining Vectors
We're hoping you know how to add and subtract. Scientists often use vectors to represent situations graphically. When they have many vectors working at once, they draw all the vectors on a piece of paper and put them end to end. When all of the vectors are on paper, they can take the starting and ending points to figure out the answer. The final line they draw (from the start point to the end point) is called the solution vector. If you don't like to draw lines, you could always use geometry and trigonometry to solve the problems. It's up to you.
Real World Vectors
Imagine a situation where you're in a boat or a plane and you need to plot a course. There aren't streets or signs along the way. You will need to plan your navigation on a map. You know where you're starting and where you want to be. The problem is how to get there. Now it's time to use a couple of vectors. Draw the vector between the two points and start on your way. As you move along your course, you will swerve a bit. Just go back to the map, find your current location, and plot a new vector that will take you to your destination. Captains use vectors (they know the speed and direction) to plot their courses.
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